Chinese medicine is the treasure of traditional Chinese culture and should be inherited and carried forward. How to correctly understand the toxicity of Chinese medicine is an important guarantee for safe use of medicine. The application and research of Chinese medicine toxicity has a long history, and the Chinese medicine community has never stopped exploring the problems related to Chinese medicine toxicity. In the ancient times, the meaning of poison and medicine were similar, and poison was often used as a generic term for “medicine bait”. During the pre-Qin period, there was a record that “the physician was in charge of the administration of medicine and gathered poisons for the medical service” in the Zhou Li Tian Guan Tsuzai. With the development of society, the understanding of Chinese medicine has been deepened and the concept has gradually changed. Some physicians believe that the partial nature of drugs is toxicity. As the Ming dynasty medical doctor Zhang Jiebin said in the “class”: “medicine to cure disease, to poison as able. The so-called poison, because the odor of the bias also. It is believed that the use of the bias of drugs to eliminate disease and evil, harmonize the functions of the internal organs, correct yin and yang, and enhance the ability to resist disease reflects the basic principle of Chinese medicine “treating bias with bias” is the basic principle of drug treatment. After the Qin and Han dynasties, the concept of “poison” in traditional Chinese medicine gradually shifted from broad to narrow, and from vague to precise; in the Sui dynasty, Chao Yuanfang’s “Treatise on the Origin of Diseases” also clearly pointed out that “poison” is the toxic side effects of medicine, saying: ” All medicines that are toxic and poisonous can be disorderly and harmful to people, and can also kill people.” The earliest extant pharmacological monograph, Shennong Ben Cao Jing, divides herbal medicines into upper, middle and lower grades, the upper grade being “non-toxic”, the middle grade being “toxic or non-toxic”, and the lower grade being “multi-toxic”, which is based on This is based on the non-toxic and toxic nature of the drugs. By and large, the drugs that attack diseases and heal illnesses are called toxic, while the drugs that are taken for a long time to supplement deficiency are regarded as non-toxic. Toxic drugs have strong effects after use. Therefore, Zhang Jinyue cloud: “medicine to cure disease, because poison for can; the so-called poison is to smell of bias also …… can ward off evil and safe, can be called poison, so it is called poison to attack evil.” Zhang’s discussion further explains the broad meaning of poison, and clarifies that toxicity as one of the drug properties, is a bias, to correct bias is also the basic principle of drug treatment. In the Materia Medica and many later books on traditional Chinese medicine, the terms “major toxicity” and “minor toxicity”, which are labeled under the nature and taste of drugs, mostly refer to drugs with certain toxicity or side effects, which can lead to poisoning if used improperly. The modern concept of toxic Chinese medicine is mostly narrowly defined, referring exclusively to those that contain toxic ingredients and are so harsh that they can easily cause toxic side effects or even kill people when they enter the body. With the development of modern science and technology, the pharmacodynamics, safety evaluation and pharmacokinetic research of toxic Chinese medicines should be strengthened on the basis of the valuable experience of the predecessors in using, preventing and suppressing toxicity, so as to gradually clarify the toxicity of various toxic Chinese medicines and the amount of starting effect, extreme amount and relief measures, etc., so as to reduce the blindness of the application of toxic Chinese medicines and make the safe use of medicines on the basis of science. Shao Kuiqing, Department of Urology, Xiyuan Hospital, Chinese Academy of Traditional Chinese Medicine In the thousands of years of development history of Chinese medicine, toxic Chinese medicines have always had an important place, and our ancestors did not put them away because they were toxic, but took a positive attitude and accumulated many valuable experiences from various aspects through continuous practice and exploration. Due to the limitations of history, it was impossible for the ancients to give a scientific explanation of the toxicity of Chinese medicine, and they could only borrow the theories of yin and yang, the five elements, sound and color, and gas, and believed that the toxicity was born from the violent energy of the five elements. It is a medicine with three points of “poison”. If the evidence is wrong and the dose of toxic Chinese medicine is not properly controlled, the patient can be poisoned. Chinese medicine can play a preventive and therapeutic role, but at the same time it can also damage the human body, leading to disorders of physiological functions and even changes in tissue structure. At the same time, understanding the toxic, non-toxic, major and minor toxicity of drugs can help us to understand the fierce or moderate effects of drugs, so that we can choose the appropriate drugs and determine the dosage according to the actuality and the depth of the disease, and reduce or eliminate the harmful effects through the necessary preparation, compounding and preparation, in order to ensure the safety of drug use.